Currently, vertical-cavity surface-emitting laser (VCSEL) devices are in practical use as a type of semiconductor laser. Hereinafter, a vertical-cavity surface-emitting laser device will be referred to as “VCSEL device”.
A VCSEL device has a general structure in which, as disclosed in Japanese Unexamined Patent Application Publication No. 2007-250669, for example, a first distributed Bragg reflector (DBR) layer is formed on top of a base substrate. A first spacer layer is formed on top of the first DBR layer. An active layer with quantum wells is formed on top of the first spacer layer. A second spacer layer is formed on top of the active layer. A second DBR layer is formed on top of the second spacer layer. An anode electrode is formed on top of the second DBR layer. Application of a driving signal between the anode electrode and a cathode electrode, which is in electrical continuity with the first DBR layer, produces laser light that has a sharp directivity in a direction perpendicular to the substrate (parallel to the stacking direction).
As described above, in a VCSEL device, the above-mentioned layers are stacked on the surface of the base substrate to form a multilayer body, and laser light is emitted from the surface of the multilayer body. The VCSEL device is mounted onto a mounting circuit board having external circuitry, in such a way that its base substrate side abuts on the mounting circuit board.
Therefore, when mounting a VCSEL device on a mounting circuit board, a die bond agent is previously applied to the position on which the VCSEL device is to be mounted, and the VCSEL device is placed on the applied die bond agent.
At this time, the VCSEL device is mounted as follows. First, the VCSEL device is picked up by a die collet or the like from its pre-mounting location (such as the surface of a dicing tape). The VCSEL device is carried to a mounting position on the mounting circuit board while being picked up by the die collet. Then, the VCSEL device is placed on the die bond agent by the die collet.